Because the region around New Orleans is composed of alluvial soil, there is no paving material close at hand. 新奥尔良一带多为冲积土,因而附近没有可用的铺路石材。
Yet the soft alluvial sediment of Tokyo's low-lying areas, it is now understood, is vulnerable to liquefaction, in which violent movement turns the soil to quicksand. 人们现在意识到了,东京的一些地势低的地方,松软的冲积土很容易受到液化作用的影响,强烈的运动会使土壤成为流沙。